Circuit controlling device



'May-5, 1947 H. T. sPARRow ETAL 2,420,105

CIRCUIT CONTROLLING DEVICE Filed 001.. 30, 1944 3 Sheets-Sheet 1 HEL/7 YGttorneg May 6, 1947 H. T. sPARRow Erm.

CIRCUIT CONTRQLLING DEVICE Filed Oct. 30, 1944 3 Sheets-Sheet 2Snventors w wm FC m WM fm we H Gttorneg May'6,1947. m. SPARROW mL2,420,105

CIRCUIT CONTROLL'ING DEVICE `Filed oct. so, 1944 y :s sneetssneet sPatented May 6, 19547 regalos CntCUrr Con'rRoLLmG DEVICE Hubert T.Sparrow and Benjamin Cyr, Minneapolis, Minn., assignors toMinneapolis-Honeywell Regulator Company, Minneapolis, Minn., a.corporation of Delaware uApplication October 30, 1944, Serial No.561,008

(C1. .zoo-16) 1: Claims. l

tor and ignition means or, for the operation of other control members ofthe furnace when it is desirable to vary the controls or circuitsdependlng upon a change of temperature of the gases of combustionpassing through the stack. ySuch devices have a portion made ofexpansible metal extending within the stack, which expands or contractswith a noticeable change of temperature. The force generated by thisaction is used to control the operation of the mechanism for opening andclosing the circuits to the various electrical devices. Because thereare great variations in the temperature existing within the stack of afurnace, as for example, before a flame is established, when thecombustion temperature has reached its safe upper limit, and again afterthe existence of combustion where there has lbeen flame failure or, whenthe temperature within the combustion chamber has fallen to a pointwhere additional fuel should be added, the device must be capable ofgiving the desired reaction at the proper time. This result is generallyobtained through a slip friction or lost motion mechanism, wherein afterthe desired switching effect has been obtained, continued movement ofthe slip friction mechanism in either direction, which may be the resultof either expansion or contraction, will not be injurious tov either theexpansible metal unit or the switching mechanism, the excessive movementof the mechanism being absorbed as lost motion. To be effective, acontrol device of this type must be highly sensitive to temperaturechange andthe switching mechanism must be capable of acting with aminimum amount of ciort.

In the present application, the device is so arranged that in the coldcontact position, the switch makes contact with three contact points,two of which are situated in a different transverse plane from theremaining contact so that y on initial movement the switch is moved awayfrom one of the contacts by the action of the biinetal when it isinfluenced by a rise in temperature of the spent gases, then oncontinued supplying mechanism.

movement in the same direction, it successively makes a circuit througha pair of hot contact points before opening the remainder of the coldcontacts. This operation serves to shunt out a 2 first circuit andestablish a holding circuit through the hot `contact points. On reversemovement of the operating mechanism, the switch controlling' the secondor holding circuit is moved to open circuit position and then, after atime lapse, the rst switch sequentially assumes its positioninengagement withthe several cold contact points. In the application ofthis device to a furnace, the sequence of the return of the first switchto its several cold contact points is timed to provide a complete breakof the operating or holding .crcuitand a scavenging period of thecombustion chamber before re-ignition,`so as toprevent a possibleexplosion of the unburnt fuel, which is present in the combustionchamber from the original operation of the fuel .Although theapplication in this instance is explained in conjunction with a fluidfuel burning furnace, it will be understood by those skilled in the art,that it is applicable to other uses where the control of electriccircuits or other pilot means are dependent upon a change of condition,which change will cause the expansion, contraction, or movement of amechanism.

The principal object of my invention is to provide an improved circuitcontrolling means which will become operative upon the change of acondition.

Another object is to provide a circuit switching device operable upon achange of condition for providing sequential and simultaneous switchingupon movement in one direction, and a complete opening of the circuitfollowed by a successive remaking of the original circuit on movement inthe other direction,

Other objects and advantages will become apparent from the specicationand appended drawings, in which Figure 1 is a plan view 0f the controlpanel;

Figure 2 is a cross section of the device taken on the line 2-2 ofFigure 1, showing the relationship between the expansible metal unit andthe switching mechanism;

Figure 3 is a detail view of an enlargement of the switching mechanism;

Figure 4, taken on the line 4--4 of Figure 3, is a cross section of thecold contact points;

Figure 5, taken on the line 5--5 of Figure 3, is a cross section of thehot contact points, and

Figure 6 is a schematic drawing of an 'oil burner control systememploying 4the device of the present reference numerals indicate thesame parts, in Figure l, reference numeral l is employed to indicate apanel upon which the various mechanisms are afxed. Suitably mounted onpanel is a conventional relay a conventional transformer |2, aconventional terminal receiving member |3, and a safety cut-out switchI4 having a manual reset member i5. Also shown in nFigure l is anactuating mechanism indicated by the general reference numeral I6 whosefunction is to operate a switching mechanism indicated by the generalreference numeral |1.

Referring now to Figure 2, tube 20 is suitably mounted on the rear ofthe panel l0 and secured thereto by flanged portions 2|. The tube 2@ isintended for mounting in the stack of an oil burning furnace or the likewith suitable flanges (not shown) and is provided with a series oflongitudinal apertures 22 whereby the tem-4 perature of the spent gasesof combustion may come in contact with a temperature responsiveactuating member. A bimetallic element 23 built in the form of a lazy Wand seen in proie in Figure 6, is suitably mounted at one end of thetube 2i] by a screw 24. At its other end of the bimetallic element isfastened by a screw 25 to a rod which extends through the tube 20 towardthe base member ill. Because of the angular disposition between the rod26 and the actuating member 28, a spring 21 is mounted on the upper endof rod 26 and serves as a form of universal joint between the rod 26 andan actuating tubular shaft 28 which extends through the panel EG. A pairof switch actuating clutchesl 2Q and 3% are situated on the shaft 28 toprovide a switch actuating mechanism which will be describedhereinafter. Each of these members 2S and 3S has a bent portion 3| and32 and each of the members also has an aperture 3S and 34 at the bentportions 3l and 32 whereby the members 29 and 30 are mounted in aslipfrictional manner on the shaft 28. Insulating strips 35 and 35 areriveted on the members 26 and 5G respectively.

rEhe construction of the members 29 and 30 having bent portions 3|, 32and apertures 33, 3Q, is to provide slip frictional engagement with theshaft 28. lNl'len shaft 28 is moved in one direction, as for example, tothe left as seen in Figure 2, members 29 and 30 will each be infrictional. engagement with the shaft and will move in unison with ituntil their further movement is individually prevented by stopping orlimiting means; thereafter, shaft 28 is free to continue movementthrough the apertures 33, 34. However, on reverse movement of shaft 23the members 29 and 30 will again move in unison with the shaft untilmovement in the new direction is again arrested, after which shaft 28 isagain free to continue its further movement through the apertures 33 and34. By this arrangement the members 29 and 3B can each be moved asufficient distance to accomplish their individual function and furthermovement of shaft 28 will result in lost motion, without danger or"damaging the members or the switching mechanism which they control.

The structure indicated by the general reference numeral i6 consists ofa generally U- shaped bracket 31 which is suitably mounted on the panelI0. The bracket 31 is provided to laterally confine the switch actuatingclutches 29 and 33 and to provide certain meansjfor limiting 'the extentof movement of these actuating clutches. A pair of slidably adjustablestop 4 members 38 and 39 are fastened to the bracket 31 by screws 40.These members are provided to limit the extent of movement in onedirection of the clutches 29 and 30 and are each provided with a slotwhereby their respective positions on bracket 31 may be made adjustable.An adjustable stop member 4| is hingedly mounted on pin 42 between therespective sides of bracket 31 to limit the extent of movement of clutch3|) in an outward direction. Thus the clutch 30 which is extended tohave a greater range of movement than clutch 29 is limited in itsmovement in one direction by the yoke 4|, and in the other direction bythe stop member 39. A lever 43 which constitutes a manually adjustableextension of stop member 4| extends through an aperture 44 in bracket 31to indicate its position on an index 45. A washer 46 is clamped on theend of the actuating shaft 28 and serves to prevent accidentalseparation of the clutch 30 from the shaft.

The switching structure indicated bythe general reference numeral I1 andshown in enlarged form in Figure 3, consists of a hollow casing 59 andan inner tubular member 5|. 'I'he members 50 and 5| are formed ofinsulating material and are secured to the panel I0 by means of screws52 extending through the flanged portions 53 of the members 50 and 5|(shown in Figure l). The casing 50 is provided with a. bushing 54 andthe inner member 5| is provided with a disk 55 having an aperture 56.The bushing 54 and aperture 56 are intended Ato provide bearing surfacesfor certain moving parts of the switch to be disclosed later. The member5| is provided with a thick annular portion `51 which serves as acontact supporting member. Radially disposed about the outer end ofportion 51 are three contact points 58, 59 and -60 (see Figure 4), whichare insulatingly mounted and connected to individual metallic conductors6|. It may be observed in Figure 3 that contact points 59 and 6D are ofsubstantially the same length but contact point 60 is shorter in lengththan the others, which is provided for a purpose to be disclosedlater.On the inner side of the annular portion 51 (see Figure 5) are providedtwo contact points 62 and 63 which are also connected to individualconductors 6| in the same manner as contacts 58, 59, and 60. The firstplurality of contacts 5B, 59, and 60 constitute a combinationhereinafter referred to as the cold contacts" and are engageable by oneswitch, while contacts 62 and 63 constitute a .second combinationhereinafter referred to as the hot contacts" andare engageable by asecond switch.

Mounted within the casing 5|) and adjacent the cold contacts is a diskswitch 65 which has a centrai aperture `64. The switch 65 is arranged tobe resiliently mounted on a rod 66 which extends through the aperture64. a spring 61 is fastened at one end to a bushing 68 which nts withinthe aperture 64 and at the other end the spring is Afastened tocollar-like structure 69 which engages the end of rod 6l. Thisarrangement permits the switch 65 to be moved by the rod l66 and permitsa certain amount of Wobbling movement, vfurthermore after the switch hasengaged the contacts, further movement of the rod causes expansion ofspring 61 as a form of lost motion and which also provides pressure onthe contacts without injury to `the To accomplish this,

rod 12 within the enclosure formed by portions 55 and 51 and adiacentthe hot contacts 62 and 63. Switch if! is provided with insulation a andis resiliently mounted with spring 01a, bushing 58a, and collar 69a inthe same manner as switch B5. An expansion spring '|3 is positionedbetween switches 65 and 7| and is intended to maintain the two switchesin spaced relation to each other and to provide one means of moving thetwo switches.

The operation of the switch is as follows: Assuming the bimetal 23 shownin Figure 2 is cool, the actuating mechanism, represented by the shaft28 will be at rest at the extreme right p0rtion of its range ofmovement. The actuating clutches 29 and 30 are engaged with the'rods 65and 12 and will be held in spaced relation by the tension of spring i3.Switch disk 65 is resiliently held in engagement with the cold con'-tacts by spring `(il and because contact 60 is shorter or situated on adiilerent transverse plane with respect to the direction of movementofthe switch as related to the other contacts 58 and space thermostat, thelatter being normally posaid switch 95 will be in tilted or angularposition. The switch disk iii is at this time held from the hot contactsby the expansion spring i3. On an impulse caused by a change ofcondition, as by a rise'of temperature of the spent gases passingthrough the stack, the b'- ment, causes switch, to move away from itsitilted position wherein it engages contacts 50,

and 59, into a fiat position where it only engages the latter twocontacts. As the movement ci the shaft 28 continues, as by a continuedexpansion of the bimetal switch 'il will then move into engagement withcontacts 62 and '63. This action, however, takes place while switch isstill engaged with contacts 58 and 59,A and in fact takes place whileswitch 65 is moving from a tilted to a horizontal position with respectto the cold contact points. Thereafter on continued movement, switch G5becomes disengaged from contacts 58 and 5t. The purpose of thisarrangelment is to provide a sequential or step by step operation of.switch S5 with respect to contact 60 and then later with contacts 58and `59 and also to provide a successive operation of thetwo switcheswith respect to contacts 58, 59 and 82, The closure of switch 7| withcontacts l62 and 53 establishes an operating circuit which will bedisclosed later, but for the time being it is suiiicient to pointentthat switch 'Il will remain in engagement with contacts |62, G3 as longas the combustion temperature maintains the bimetal 23 in an expandedcondition. For safety reasons it is essential that when the temperaturewithin the combustion chamber descends, switch disk 1| must breakengagement with the hot contacts before switch disk 65 again engages thecold contacts. Therefore, as the bimetal 23 contracts, the firstincrement of movement of the actuators to the right, as shown in Figures2 and 3, causes switch disk ll :to move away from contacts 62, 63, andthereafter as the movement continues switch disk t5 will initiallyengage consitioned in the space to be heated..

The space hermostat |00 is shown as a conventional thermostat having twoblades |0| and |02. Blade |0| is positioned to cooperate with contact Y|03 carried by conductor |40, and blade |02 is positioned to cooperatewith contact |05 carried by conductor itl. A

The safety switch 4 is provided with blades |05 and |06 having contacts|01 and |08. Blade |06 is held in engagement with blade |05 by abimetallic blade |09. A heating element i|0 is positioned adjacent thebimetal |09 and is provided to radiate and conduct heat to the bimetal09 thus causing it to warp to the rightand separate blade E08 from blade|05, in the event that the circuit through the heating element iidexists for an excessively long period of time. rlhis is a conventionalmethod of breaking the circuit in the event of ignition failure, Whenthe blades have been separated as by the warping of the bimetal its, toprevent the continuation ci an unsafe condition, they will not, oncooling, replace themselves, To accomplish this an actuator i isprovided. 'When the binietal @dit has cooled, manual movement of theactuator brings the contacts itil", itil into engagement permits bimetalit@ to assume its normal position supporting the blades |155, i Elfi.

The sten-down transformer i2 is provided with a primary coil iii and asecondary coil itil and is intended to provide low voltage current forthe operation of various portions of the control mechanism. ConductorsH3 and iiio; connect the primary' coil iii to line voltage conductorsM4, H5 which convey line voltage electric cnrn rent (from a source notshown) rlhe control -device is intended for controlling the' linevoltage circuit furnished by the conductors liti, M5 for the operationor' any electrically controlled fuel burning furnace having electricalignition means. As there are many commercially ,available forms of thesestructures, they are diagrammatically illustrated as a motor H6 andignition means ||1.

llhe relay is intended for controlling numerous circuits ci'Y both lineand low voltage currents and is provided with an induction coil i20which when energized, through an armature movement indicated by thedotted line i20a causes switch i 2| to engage contact |22 to provideline voltage to the motor ||5 and ignition means ||1. it also causesswitches i23, |25, and |25 to engage contacts |26, |21 and |28 toprovide low voltage circuits between the'severai elements of the controldevice.

Assuming the elements to be in the position shown in Figure 6, thetemperature in the controlled space is above the minimum requirementsand the thermostat is inclined in the direction of the legend H whichindicates a. satisfied condition, and the motor I6 and ignition meansare inoperative. Now assume the temperature in the controlled spacedescends below that for4 which the thermostat is set. The thermostatblades will then incline in the direction of the legend C. Initiallyblade |0| will engage contact 503 but because the circuit does notinclude 'cir'cuit cannot be completed; However, on a contact.|03, bladesand |02 of thermostat |00, contact |04, conductors |4| and |42 tocontact 60, switch 65, contact 58, conductor |43, heating element ||0,conductor |44, blade |08,

Icontacts |08, |01 and blade |05 of the safety switch i4, thence throughconductor |45 to coil |20 and thencel through conductor |46 back to thesecondary 2. Energization of inductance coil |20 will cause closure ofswitch |2| with con- I tact |22 to establish a line voltage circuit forthe operation of the motor and ignition means, which may be traced asfollows: from conductor H4, to conductor |41, contact |22, switch |2|,conductor |48 to the ignition device ||1, to conductor |5|, to conductorl i5, and by branch |49 to motor I0, thence by branch |50 and conductor|5|, to conductor H5, to compltethe circuit for the operation of themotor and ignition means. Simultaneous with the closure ofy the linevoltage switch, switches |23, |24 and |25 move into engagement withcontacts |28, |2'i, and |28 to complete low voltage circuits to beexplained later.

es the temperature of combustion gases increase, the bimetai 23 expandsand the shaft 28 and actuating clutches 29 and 38 to move to the left asseen in the several figures of the draw- Wth the first increment ofmovement, switch 65 moves from its tilted position away from contact 60.This action causes conductor |42 te become inoperative with theiatentpurpose of preventing a rapid remaking of the circuit in the eventof flame failure but has no iinmediate eect upon the circuit sincecurrent may now pass across switch B5 between contacts 58 and 59 andcomplete the circuit through conductors ii, |55, contact |21, switchblade |24, conductor |54, switch blade |23, contact |26, conductor |59,conductor |52. With the continued movement of the actuating mechanismI1, switch 1| engages contacts 62 and 63. It should be understood thatat the instant switch disk'1| engages contacts 62 and 63, switch 65 isVstill engaged with contacts 58 and 59, however, substantiallyimmediately thereafter switch 85 does disengage from contacts 58 and 59but the time delay is only suiicient to provide a proper overlapping ofthe two switching actions. Thev purpose of this' switching action was toshunt out; `the heater |0 of the safety switch I4 whose purpose is tobreak the circuit in the event of failure of ignition, and establish anoperating circuit which may may be traced as follows: from secondary H2,conductor |40, contact |03, blade |0| of thermostat |00, conductor |56,contact |28, switch blade |25, conductor |54, switch blade |23, contact|26, conductors |53 and |51, contact 63, switch disk 1|, contact 62,conductor |58, safety switch blade |06, contacts |08, |01, blade |05,conductor |45, induction coil |20, and conductor |46 to the other sideof secondary coil ||2 of transformer |2.

Should there be flame failure resulting from any cause after combustionhas been established,

and While the space thermostat |00 is still calling for heat, thebimetal 23 will commence to contract and through theconnecting linkagewill cause the actuating mechanism |1 to move to the right as seen inthe several figures. At this stage it would be highly undesirable topermit the immediate reformation of the starting circuit through switch65 for the reason that the unburned fuel remaining in a gaseous state,might cause an explosion. Therefore, with the first increment nfmovement of the actuating mechanism caused by retraction of the bimetal23, the switch 1I moves away from contacts 62 and 83^to disrupt thecircuit. When thecircuit is broken the relay moves to aninoprativeposltion opening switch |2| from contact |22 to thereby causetheymotor ||6 and ignition means ||1 to become inactive. It will alsocause switches |23, |24, and |25 to move away from their respectivecontacts |26, |21 and |28 to thus disrupt the operating circuit. As theswitch 65 then continues its movement to the right, it will first engagecontacts 58 and 59, but this will not complete a circuit even though thethermostat |00 is still calling for heat and the blades |0| 'and |02 areengaging contacts |03 and |04 because`it is essential that the switch 65engage contact 60 before this action can take place. Thus, thestep b'ystep movement of the switch 65, with respect to contacts 58, 59, and 60,provides a sufficient time lapse to enable the unburned gases to escapefrom the furnace before the completecircuit can be remade. This periodof time is commonly referred to as the recycling period and in thepresent device it may be made adjustable for the particular application,by moving the yoke-4|, positioned near the outer end of bracket 31. Thismember adjusts the distance which the clutch 30 must travel during theheating period and therefore the distance which it must travel on thereturn movement. However, in the event that this distance is short, thefurther movement of the switch 65 in assuming its tilted positionagainst contact 60 will prevent an immediate remaking of the startingcircuit which therefore accounts for the reason that the contact 60 isshorter in length or positioned on a rdifferent transverse plane thancontacts 58 and In considering the switching mechanism and its coactingparts, it will be evident that a combination of sequential andsuccessive actions takes place which may have wider use than in thesingle disclosure of this application; therefore, I do not wish to belimited to the single use disclosed herein, but rather only by the fullextent of the'appended claims.

We claim as our invention:

i. A circuit controlling device, comprising, a contact supportingmember, three contacts mounted in spaced relation to each other on oneside of said supporting member,v one of said contacts beingrspaced on adifferent transverse plane than the remainder, a single switch adaptedto collectively engage all three of said contacts, and said switch beingresiliently mounted for engaging and/or disengaging said contacts in aseries of sequential steps.

2. In a circuit controlling device, comprising, a contact supportingmember, three contacts mounted on one side of said supporting member,one of said contacts being disposed on a different transverse plane thanthe remainder, a first switch adapted to collectively engage all threeof said contacts, another Contact mounted on the` opposite side of saidsupporting member, a second switch located on the opposite side of saidsupporting member from said first switch and being adapted to engagesaid other contact, means for moving said first and second switches inunison with relation to their` respective contacts, and means for movingsaid first switch in a. step by step sequence with 'respect to theseveral transverse planes in which said three contacts are situated.

3. In a circuit controlling device, comprising, a contact supportingmember, a plurality of contacts mounted on one side of said supportingmember, one of said contacts beingdisposed on e. different transverseplane than the remainder,

A- a rst switch adapted to collectively engage all oi. said plurality'of contacts, another contact mounted on the opposite side of saidsupporting member from said plurality of contacts, a second switchlocated on the opposite side of said supporting member from said rstswitch and being adapted to engage said other contact, a resilientconnection between said iirst and second switches for maintaining saidswitches in spaced relation with each other, means for-moving saidswitches in unison with relation to their respective contacts, andresilient means connecting said rst switch and said rst named means formoving said switch in a step by step sequence with respect to thetransverse planes in which said plurality of contacts are situated.

d. ln circuit controlling device, comprising, a cciiitact supportingmember, a rst plurality of contacts mounted on one side ci saidsupporting member, a first switch adapted to engage said rlrst pluralityof contacts, a second plurality ci" contacts mounted on the oppositeside of said sup-porting member from said ilrst plurality of contacts, asecond switch adapted to engage said second pl switches in unison withrelation to their re spective contacts, said. supportingmcmber hav'waperture, means passing through the aperturc in said supporting meanswhich is connected its opposite ends to said two switches and isoperative upon movement ofsaid switches in one ecticn to move saidsecond switch into engagement with said second plurality of contactsbeiore said nrst switch has completely disengaged from said iirstplurality of contacts, and said being operative on reversal of movementci* said. switches to inove said second switch away ,trom said secondplurality of contacts before said first switch has completely engagedsaid first plurality ci* contacts. l

5, lin a circuit controlling device, comprising, a contact supportingmember, a rst plurality of contacts mounted on one side otsaidsupporting member, one of said contacts being located n a diuerenttransverse plane than the remainder, a

second plurality of contacts located on the oppostte side of saidsupporting member from said first plurality of contacts, a first switchand a second switch for respectively engaging said first and secondplurality of contacts, rst and second switch moving members slipfrictionally connected to an actuating member for moving said switcheswith relation to their respective contacts in response to movement ofsaid actuating member and means including a resilient member connectingsaid first switch and said rst switch moving member to move said iirstswitch in a step by step sequence with respect to those contacts whichare situated in different transverse planes.

6, ln a circuit controlling device, in combination, a contact supportingmember, a Ifirst plurality oi contacts mounted on one side ofk saidmember, one of said contacts being mounted at o diiterent distance fromsaid supporting memaiity ci? contacts, means for moving ber than theremainder of said contacts, a sec,-

' biasing said switches in spaced relation with each othena rodresiliently attached to each switch, a pair of frictionally mountedactuators for cooperating with said resiliently attached'rods to movesaid switches with relation to said contacts, said actuators having afirst position in which said rst switch is in tilted engagement withsaid rst plurality of contacts and said second switch is disengaged fromsaid second plurality of contacts, and means for moving said actuatorsto disengage said rst switch from a portion of said rst plurality ofcontacts and successively engage said second switch. with said secondplurality of contacts before said rst switch is disengaged from theremainder of said first plurality of contacts. A

7. In a circuit controlling device, in combination, a contact supportingmember, a iirst plurality of contacts mounted on one side of saidmember, one of said contacts'being mounted at a dierent distance fromsaid supporting member than the remainder' of said contacts, a sccondplurality of contacts mounted on the opposite side of said supp Jrtingmember, a iirst switch and a second switch adapted to respectively' en"gage said irst and second pluralities of contacts, resilient .meanslocated between said switches for i biasing said switches in spacedrelation with each other, a rod resiliently attached to each switch, apair of irictionally mounted actuators for cooperating with saidresiliently attached rods to move said switches with 'relation to saidcontacts,

, said actuators having a first position in which said second switch isin engagement with said second plurality of contacts and said rst switchis disengaged from said first plurality of contacts, and means formoving said actuators to disengage said second switch from said secondplurality of contacts before said first switch commences to successivelyengage said first plurality of contacts.

d. In a circuit controlling device, comprising, a contact supportingmember, a plurality of contacts extending from .said supporting member,one of said contacts extending a different length trom said supportingmember than the remainder, a movable conductor for transmitting currentbetween said contacts, an actuating member for moving said conductorwith relation to said contacts, a resilient member connecting saidconductor about its center to said actuating member in such a manner asto provide angular tilting movement of said conductor about its centerwith respect to said actuating member, said conductor being adapted toassume a tilted position with respect to said actuating member` when inengagement with all of said contacts, and said resilient connectionbeing adapted to move said conductor away from said contacts in a stepby step sequence when said actuating member moves away from saidcontacts.

9. In a circuit controlling device, comprising, a tubular supportingmember, a plurality of contacts radially disposed about the periphery ofsaid tubular member, one of said contacts being situated on a diierenttransverse plane than the remainder, a switch for simultaneouslyengaging all of said contacts, said switch having an aper ture thereinwhich coincides with the tubular switch mounted on opposite sides ofsaid supl12"l ber from said ilrst contact, a rst and second portingmember for cooperating respectively with said first and secondcontacts.' a movable actuating rod located adjacent saidl supportingmember, a'flrst'and second switch actuating. members slip'fx'ictionallymounted on said rod and and will then assume a tilted position to engagethe remainder of said contacts.

10. A switching device, comprising, a body member having an aperturetherein, a contact mounted on said body member adjacent said aperture, amovable switch member adapted to cooperate with said contact, saidswitch member having an aperture which coincides withl said bodyLaperture, an actuating rod extending through the aperture in said switchmember, and resilient means associated at its opposite ends with saidswitch and said actuating rod whereby after saidlswitch has engaged saidcontact continued movement of said actuator produces lost motion.

1l. In a circuit controlling device, comprising, a Contact supportingmember, a plurality of contacts extending from said supporting member,one of said contacts extending a different length from said supportingmember' than the remainder, a movable conductor for transmitting currentbetween said contacts, an actuating member for moving said conductorwith relation to said contacts, a resilient member connecting saidconductor about its center to said actuating mem ber in such a manner asto provide angular tilting movement of said conductor about saidactuating member, and said conductor` when moved in the direction ofSaid supporting member completely engages all of said contacts in asuccessionof steps which includes tilting about its center on saidactuating member to engage said one contact whose length from saidsupporting member differs from the remainder.

12. In a circuit controlling device, a supporting member, a iirstcontact mounted on one side of said supporting member, a second contactmounted on the opposite side of said supporting memcooperating with saidswitches in such a manner that upon movement of said rod in one diswitchis moved away lfrom its respective contact.

13. In a circuit controlling device, a supporting member, a pair ofcontacts each of which is mounted on respectively opposite sides of saidsupporting member, a pair of switches each of which is located onopposite sides of said supporting member and adapted to cooperate with are spectively opposite contact, connecting means located between saidpair of switches for maintaining said switches in spaced relation toeach other, a movable actuating member locatedadjacent said supportingmember, and a. pair of switch moving members slip frictionally connectedto said actuating member and being positioned with respect to saidswitches that upon movement of said actuating member for a'predetermineddistance both of said switches are moved simultaneously with respect totheir cooperable contacts, l

HUBERT T. SPARROW. BENJAMIN CYR.

REFERENCES CITED The following references are of record in the iile ofthis patent:

UNITED STATES PATENTS Number lName Date 2,175,720 Miller -4. Oct. 10,1939 2,159,503 Denison May 23, 1930 2,191,742 Miller Feb. 27, 1940

